Some products are delivered and sold in containers for use by customers. For example, propane is often sold in containers that are cylindrical canisters having valves, such as the type typically used for outdoor grills. These canisters typically have a cylindrically shaped tank, a base-mounted to the bottom of the tank, a valve at the top of the tank, and a guard substantially encircling the valve and providing a pair of lifting handles. The base and the guard typically have diameters smaller than the diameter of the outer surface of the tank. Because of the specific nature in which such canisters must be filled, the equipment needed to fill the tanks, and the highly combustible nature of propane, it is generally required that a professional fill a user's propane tank.
Accordingly, for propane and similar products, empty canisters are typically exchanged for full ones. Generally, when a canister is empty (i.e. substantially out of propane or other product), a user brings the substantially empty canister to a particular store and exchanges the empty canister for a full canister (i.e. full or substantially full of propane or other product). Or, the user may buy a substantially full canister without exchange of an empty canister. A cashier generally assists the user in accessing the full canister and/or ensuring that the user returns the empty canister and accesses a full canister.
The term “substantially” when used with the term “full” herein means the canister is full within a range of capacity of the canister to hold its contents within a safety margin for the canister and/or as set by the distributer or dealer, which may vary. Additionally, some canisters thought to be “empty” by a purchaser may still contain propane. The term “substantially empty” as used herein may describe a canister discerned as empty or desirable for exchange by a purchaser.
Typically, the user pays for the full canister first, and then the canister is distributed post-payment. This is different than the usual indoor retail environment, where goods are gathered first and then paid for by the customer.
The full and empty propane canisters may be kept in various secure locations (e.g. locked cage, etc.). Additionally, the propane canisters are generally also stored outside the store for various safety reasons. Storage of propane canisters is typically regulated by local, state, or federal government agencies, or under best-practice safety guidelines. For example, the use of electrical components that could cause a spark could be restricted near the stored propane. Such regulations may be promulgated by agencies and associations such as the federal Occupational Safety and Health Administration, the Compressed Gas Association, the National Fire Protection Association, the American Petroleum Institute, the International Electrotechnical Commission, and the Canadian Standards Association.
Exchanging and distributing the propane canisters can be burdensome for the businesses that sell the canisters in that the cashiers may have to leave the registers to help customers exchange the canisters or obtain full canisters. This can also result in customers waiting at the register unassisted or the businesses making an employee constantly available to exchange and distribute propane canister.
Additionally, if the cashier accepts payment and allows the customer to return and/or withdraw the canisters unsupervised, the customer may return or take the wrong number of canisters, causing inventory losses and/or discrepancies.
Fully automated systems are one answer to these problems. However, fully automated systems may be prohibitively expensive for some small businesses.